Move camera relative to view in javafx?

Question

I have a camera in my scene, which I am currently moving on the x y and z axis using WASD. However, I would want it to move according to the direction it is facing. For better illustration of what I mean, I am using snippets from the program blender to demonstrate the idea.

Image 1

In Image 1, it is quite easy. Moving forward will simply move on the x (red) axis, moving to the sides will be on the y (green) axis. The problems arise when the camera is rotated, thereby changing it's position relative to the axes, as Image 2 shows from the top view:

Image 2

If I now try to move forward (direction of the red arrow), I need the movement to accommodate for the rotation, and adjust the x and y coordinates so that the camera moves forward from it's perspective.

Is there a way of doing this? I have tried many calculations involving sine and cosine, and quite a few google searches, but it led to no result. Google mostly showed unsolved questions or solutions using OpenGL, and my math equations simply spewed out incorrect results.

I hope I explained the problem clearly, if not I will be happy to provide additional information. Thank you for your time!

Answer 1

I know im like 3 months late but I think I know what you mean.

In JavaFX you have a group called world (Everything 3d except the camera). If you want to rotate the camera to the left (example around the y axis) you don't touch the camera but the world and rotate that around the y axis.

I'll be honest I don't 100% understand why it works but it does for me (I'm working on a game so I had to go through it).

I hope this answers your question :D

EDIT 1: Sample code

package FXTesting;

import javafx.application.Application;
import javafx.scene.Camera;
import javafx.scene.Group;
import javafx.scene.PerspectiveCamera;
import javafx.scene.Scene;
import javafx.scene.input.KeyEvent;
import javafx.scene.shape.Box;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Translate;
import javafx.stage.Stage;

public class Main extends Application {

    public static int SIZEFACTOR = 100;

    @Override
    public void start(Stage primaryStage) throws Exception {
        Group world = createEnvironment();

        Scene scene = new Scene(world);
        primaryStage.setScene(scene);
        primaryStage.setWidth(16 * SIZEFACTOR);
        primaryStage.setHeight(9 * SIZEFACTOR);

        Camera camera = new PerspectiveCamera();
        camera.setFarClip(2000);
        camera.setNearClip(1);

        scene.setCamera(camera);

        Rotate worldRotX = new Rotate(0, Rotate.X_AXIS);
        Rotate worldRotY = new Rotate(0, Rotate.Y_AXIS);

        Translate  worldTransX = new Translate();

        world.getTransforms().addAll(worldRotY, worldRotX);

        primaryStage.addEventHandler(KeyEvent.KEY_PRESSED, event -> {
            switch(event.getCode()){
                case LEFT:
                    worldRotY.setAngle(worldRotY.getAngle() + 10);
                    break;
                case RIGHT:
                    worldRotY.setAngle(worldRotY.getAngle() - 10);
                    break;
                case UP:
                    worldRotX.setAngle(worldRotX.getAngle() + 10);
                    break;
                case DOWN:
                    worldRotX.setAngle(worldRotX.getAngle() - 10);
                case W: //w/s is for z
                    world.setTranslateZ(world.getTranslateZ() + 10);
                    break;
                case S:
                    world.setTranslateZ(world.getTranslateZ() - 10);
                    break;
                case A:// a/d is x axis
                    world.setTranslateX(world.getTranslateX() + 10);
                    break;
                case D:
                    world.setTranslateX(world.getTranslateX() - 10);
                    break;
                case SHIFT:// shift/contr is for y axis
                    world.setTranslateY(world.getTranslateY() + 10);
                    break;
                case CONTROL:
                    world.setTranslateY(world.getTranslateY() - 10);
                    break;

            }
        });

        primaryStage.show();
    }

    private Group createEnvironment(){
        Group group = new Group();

        Box ground = new Box();
        ground.setHeight(10);
        ground.setWidth(1000);
        ground.setDepth(1000);

        ground.setTranslateX(-500);
        ground.setTranslateZ(-500);


        Box box = new Box(100,100,100);
        box.setTranslateY(10);

        group.getChildren().addAll(ground, box);

        return group;
    }

    public static void main(String... args){
        launch(args);
    }
}